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The values of ASTM grain size numbers and percentage of nodularity across each specimen were tabulated in Table 1 and Table 2 respectively.
The tabulated results were plotted for different locations on the sample against the ASTM grain size number [Fig 3] and percentage of nodularity [Fig 4].
It was observed that ASTM grain size number and the percentage of globular grains has increased when the stirring speed was 400 rpm.
It was also observed that with the addition of grain modifier the ASTM number has increased as compared to original sample indicating that the grain size has reduced but the percentage of nodularity has increased.
ASTM grain size number for Sample 1 Nodularity% report for Sample 1 Fig 5 V.

Potential Measurement of Grain Boundary and Grain Interior.
Potentials of the grain boundary and the grain interior are shown in Fig. 2.
Precipitation State on Grain Boundary and Grain Interior.
Also, there were a number of Al15Mn3Si2 precipitates in the grain interior.
Hence, potential differences between the grain boundary and grain interior became large and IGC easily occurred.

Here, the grain morphology is the dominant one.
The second zone corresponds to columnar grain zone.
It corresponds to the zone of equiaxed grains.
· White spots (islands): observed near the grain boundaries and inside the grains.
Furthermore, a small number of tertiary dendrite arms are formed.

Watershed analysis on AFM images show that the numbers of grain boundaries in Ni/ITO are reduced when annealing temperature is increased to higher temperatures.
Annealing Temperature (°C) Root Mean Square, RMS (nm) Peak to Valley, P-V (nm) Number of Grain Boundaries, N Thickness (nm) 450 1.978 25.083 83 2.898 500 1.887 30.482 80 3.491 550 2.134 22.918 81 3.863 600 2.598 59.115 55 4.569 Fig. 2, Surface roughness and peak-to-valley of Ni/ITO for various annealing temperatures scan by AFM.
Figure 3 shows the grain boundaries of the samples using watershed method.
The numbers in the images indicate the total grain boundaries on the surface of the annealing samples.
The total number of grain boundaries decrease when the annealing temperature are increased.

In this case only these specific, slowly etched grains will have interference color, as the thickness of the interfering layer above all the other grains will pass the transparency borderline.
It is also interesting to note, that the surface of the higher grains – which are close to the (111) orientation – are smooth, while all the other grains have striped patterns.
To selectively filter the grains which are close to the (111) direction several established grain detection algorithms – such as the watershed, for example – could be used [12].
Conclusions A method to identify and quantify the number of grains which are close to the (111) orientation in a cold rolled steel sample was presented.
An effective image processing method for the identification of the grains based on the latter property was proposed and demonstrated for blue (111) grains.

Heat treatment is basically the combination of operations involving the heating and cooling of a metal or alloy in solid state for obtaining required microstructures by refining the grain size and a combination of properties.
In steels containing more than 0.8% carbon it exists as a grain boundary film.
Austenite consists of polyhedral grains showing twins.
The hardness number of the specimens was recorded before heat treatment
Its hardness number is less than hardening but greater than annealing.

Influence of grain size distribution in the cross section was also investigated.
Considering that the sample is loaded perpendicular to the cross section, stress in the cross section should be: (3) where is the stress of the layer, is the area fraction of the layer in the cross section, and is the number of layers.
In conventional polycrystalline material, fine grains can exhibit high yield stress because of the enhancement of obstacle to dislocation motion at grain boundaries.
As the grain size decreases to the order of nanometers, the grain boundaries will tend to slide [18].
In addition, it should be noted that the formation of nanostructures from coarse-grained polycrystals involves various dislocation activities and development of grain boundaries during SAMT [4].

The new fine grains appear mainly on the grain boundaries of highly elongated original grains at temperatures below 800°C, making a necklace like microstructure.
Nucleation of DRX grains at 700°C.
The new fine grains appear as cells in the network strain induced grain boundaries.
The number of strain induced grain boundaries increases with straining, leading to formation of new DRX grains, which form chains at the original grain boundaries (Fig. 3b).
Progressive development of the new fine grains at frequently serrated grain boundaries makes a mantle of RDX grains surrounding the original grains (Fig. 3d).

We then multiplied the mean number of pollen grains per anther by the number of stamens per flower to estimate the number of pollen grains per flower.
The P/O ratio was finally calculated as the number of pollen grains in one anther divided by the number of ovules.
The number of pollen grains that changed to red color per 100 pollen grains was taken as the pollen viability index [1].
The pollen grain numbers, ovule numbers, and P/O ratios for this species are given in Table 1.
The pollen grain number, ovule number, and P/O ratios for Robinia pseudoacacia Stamens no.

On the other hand, the number of research works on SPD of steels is still limited [9-16], probably because systematic SPD processing is relatively difficult in steels having higher flow stresses.
The fHAGB increased with increasing the number of the ARB cycle (strain), as was pointed out in Fig.1, and 82% of the existing boundaries were high-angle ones after 5 cycles.
The mean spacing of the high-angle lamellar boundaries also decreased with increasing strain (number of ARB cycle), and it showed nearly the same value of about 0.25 µm after 5 cycles.
During annealing, recovery at grain interior also happened at lower temperatures, and the (sub-)grains started to grow.
As strain increases, the grain subdivision proceeds and the number of the fine areas surrounded by high-angle boundaries increases.